Today's reality includes emergence and spread of multi-drug resistant organisms and new infectious agents, a growing concern for worldwide pandemics, the use of infectious agents in offensive bio-warfare, and an enlarging list of opportunistic infections. These challenges to human health necessitate comprehensive interdisciplinary training programs for the next generation of scientists in studies of the microbe host interface. The training faculty are from three colleges and several different departments. The hub for the program will be the Ohio State University Center for Microbial Interface Biology (CMIB), which is focused on Host-Pathogen Research. One of the PIs (MPI mechanism) is a physician scientist who serves as Director of the CMIB and Chair of a new Department in the Medical School, Microbial Infection and Immunity (MI&I), and the other PI is a PhD scientist and CMIB Vice-Director/MI&I Vice-Chair, both with strong research programs and careers focused on education. Thus the PIs represent an outstanding, established collaborative team to oversee this broad innovative program which emphasizes: 1) a highly interactive scientific community, 2) a multidisciplinary approach to science, 3) exposure of trainees to the biomedical research community of a large academic health sciences center, 4) integration of the clinical and basic sciences, 5) exposure to experienced and talented scientist educators and mentors, and 6) several added advantages to Fellows, including a local and international externship program. The major thematic areas are 1) Microbial response to infection; 2) Host response to infection (immunity, respiratory biology); 3) Biofilms; and 4) Drug discovery. The program describes a Selection and Oversight Committee, an outstanding, engaged External Advisory Committee and the necessary administrative structure to execute the program. Emphasis is placed on the recruitment of diversity trainees and on formal instruction for the responsible conduct of research. We request 3 pre-doctoral, 2 post-doctoral and 1 short-term clinical scholar slots/year. We believe that the curriculum, faculty, resources, and institutional support make this program attractive to outstanding students who will receive a unique multidisciplinary training experience focused on the microbe-host interface and prepare them for a career in the breadth of the biomedical workforce.